A study of Cr-doped GaAs by thermally detected electron paramagnetic resonance

Abstract
The results obtained from thermally detected EPR experiments on semi-insulating chromium-doped GaAs are reported. The main lines in the spectra show tetragonal symmetry and arise from type I substitutional Crs2+ ions in tetragonal sites. Weaker isotropic and anisotropic lines have also been found. Type II Cr does not give rise to significant spectra. The line intensities are accounted for mainly in terms of magnetic-field-induced transitions for Crs2+. Electric-field-induced transitions are very weak in GaAs.